The present invention relates to an acoustical array of hydrophones used for underwater detection purposes and, more particularly, to a roll of polymer piezoelectric transducers deployable in a variety of arrays and which arrays may be rolled up into a cylindrical shape and neatly and conveniently stored in a shaped housing, such as those cylindrical housings founds in sonobuoys.
Arrays of transducers for underwater listening purposes are well known and such arrays usually consist of rigid rods, springs and separate ceramic elements clamped to the array's structure with external wire. Such arrays have many mechanical parts and are awkward to handle. Further, the packaging of such arrays does not make effective use of available space because of the overall excessive volume occupied by the arrays themselves.
Transducers serving as hydrophones are well known and one such is described in U.S. Pat. No. 3,881,165 ('165) of Parker et. al. The '165 patent discloses a single hydrophone comprising a flexible tubular core which is dimensioned so as to be slidable within a polyvinyl chloride tubing or potted in a flexible resin coating. It is desired that means be provided for arranging an array of hydrophones having a flexible characteristic.
U.S. Pat. No. 4,187,556 ('556) of Jones discloses piezoelectric transducers that may be formed into a particular shape, so as to focus the acoustic energy into a desired band for subsequent detection and utilization by electrical circuitry. The '556 patent further discloses an arrangement of the piezoelectric elements into an array, so as to selectively gather acoustic energy for underwater detection purposes. It is desired that the features of such an array be provided, while at the same time allowing the array to be easily packaged and stowed and, then, easily placed into a deployed condition for usage by an underwater detection system.